title: Enzymatic generation of chitooligosaccharides from chitosan using soluble and immobilized glycosyltransferase (Branchzyme).
abstract: Chitooligosaccharides possessing remarkable biological properties can be obtained by enzymatic hydrolysis of chitin. In this work, the chitosanase activity of soluble and immobilized glycosyltransferase (Branchzyme) toward chitosan and biochemical characterization are described for the first time. This enzyme was found to be homotetrameric with a molecular weight of 256 kDa, an isoelectric point of 5.3, and an optimal temperature range of between 50 and 60 °C. It was covalently immobilized to glutaraldehyde-agarose with protein and activity immobilization yields of 67% and 17%, respectively. Immobilization improved enzyme stability, increasing its half-life 5-fold, and allowed enzyme reuse for at least 25 consecutive cycles. The chitosanase activity of Branchzyme on chitosan was similar for the soluble and immobilized forms. The reaction mixture was constituted by chitooligosaccharides with degrees of polymerization of between 2 and 20, with a higher concentration having degrees of polymerization of 3-8.
authors.affiliation: Departamento Bioactividad y Análisis de Alimentos, Instituto de Investigación en Ciencias de la Alimentación, CIAL (CSIC-UAM), CEI (UAM+CSIC) , Nicolás Cabrera, 9, 28049, Madrid, Spain.
authors.forename: Antonia
authors.initials: A
authors.lastname: Montilla
authors.forename: Ana I
authors.initials: AI
authors.lastname: Ruiz-Matute
authors.forename: Nieves
authors.initials: N
authors.lastname: Corzo
authors.forename: Cecilia
authors.initials: C
authors.lastname: Giacomini
authors.forename: Gabriela
authors.initials: G
authors.lastname: Irazoqui
mesh_terms: D001426:Bacterial Proteins / Q000737:chemistry*; D055162:Biocatalysis; D048271:Chitosan / Q000737:chemistry*; D004795:Enzyme Stability; D004800:Enzymes, Immobilized / Q000737:chemistry; D016695:Glycosyltransferases / Q000737:chemistry*; D006863:Hydrogen-Ion Concentration; D008970:Molecular Weight; D009844:Oligosaccharides / Q000737:chemistry*; D045245:Rhodothermus / Q000201:enzymology*; D013696:Temperature
chemical_list: D001426:Bacterial Proteins; D004800:Enzymes, Immobilized; D009844:Oligosaccharides; D048271:Chitosan; D016695:Glycosyltransferases